It is commonly believed that stressful life events make people more susceptible to asthmatic events. We propose a within subject design where volunteers are administered a bronchoconstrictor challenge once under relatively stressful conditions, once under relatively calm conditions, and once during a neutral period. The challenge will involve determining a dose-response curve for the effects, of the bronchoconstrictor on lung function as measured by FEV1. Volunteers will be randomly assigned to condition order (stress then calm or calm then stress). We will use methacoline as the bronchoconstrictor.